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FONIX 7000 Hearing Aid Analyzer
3. Use [<, >] to choose AVERAGE.
4. Use [
∨, ∧
] to select Avg Freqs under Aid Settings.
5. Use [<, >] to choose the highest frequency of the three frequency average.
See Section 2.3.1.1 for a complete list of frequencies.
6. Press [EXIT] to return to the Coupler screen. The three frequency average
will automatically be running.
7. Adjust the amplitude using the [
∧,∨
] buttons.
Figure 3.4.6—Measuring a three frequency average
3.4.7 Measuring Harmonic Distortion
Harmonic distortion is when the hearing aid returns energy at frequencies not
present in the source signal. The 7000 analyzer allows you test for this phe-
nomenon very easily.
1. Press [MENU] from the Coupler screen.
2. Select Distortion under Measurement Settings using the [
∨, ∧
] buttons.
3. Select the distortion type desired by using the [<, >] buttons.
The selections are:
2ND: Distortion present at the second harmonics, or twice the presented
frequency.
Summary of Contents for FONIX 7000
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